Economizer



Marh 10, 1931. J. VAN BRUNT ETAL ECONOMI ZER 1926 3 Sheets-Sheet 1 Filed March 11 IN VEN TORS TTORNE K5 March), 1931.

J. VAN BRUNT ET AL ECONOMI ZER Filed March 11 March 10, 1931. V R T T L 1,795,909

' ECONOMIZER Filed March 11, 1926 ISSheets-Sheet 5 INVENTORS W Patented Mar. 10, 1931 ATE r e u:

JOHN VAN BBUN'I, or FLUSHING, nanny irnnrsinenn, or Pines-roar, AND HARRY '1. BERNI-IARD, 0F NYACK, new Yon-K, ASSIG-EGR-S '18 rnrnnnnrronnn COMBUSTION. ENGINEERING-CORPORATION, or new YOB-K, n. 52., A ccaroaarron or DELAWARE Economizer;

Application filed March 11, 1926. Serial No.,98,889.

gasesor waste products of combustion. More specifically the invention contemplates the provision of apparatus topreheat air for combustion purposes, to utilize the heat of the waste furnace gases 1n so doing, and to extract from'the gases any particles of dust which would otherwise pass out the stack, and-also any coal dust "carried in suspension therein in installations where such waste gases are previously passed through a coal We further aim by our invention, through the provision of a combined air preheater and dust-collec'tor,to cutdown the frictional resistance to the furnace draft, to reduce substantially the boiler-room space required for economizingapparatus, tominimize the cost of such apparatus, and to make it possible to mount or locate such apparatus in the most convenient and space-saving way for any particular installation.

How we obtain these advantages and others on the line 22 of Fig. 1, showingthe gas and air passages, the dust-catching channels,

' and the supporting and spacing rods in cross section Fig. 3 is an enlarged line 33 of Fig. 1;'

F ig.'3a is an si milar section taken on line 3a3a of Fig. 1. v I 3 Fig.4 is a fragmentary view showing the section taken on the lower end of several ofthe dust-collecting channels and illustrating the way in which the dust is diverted into the collecting chamber; Y

Fig. 5-is a section taken on the line 55 of Fig. 4;

Fig. sis a vertical longitudinalsectional view of a modified form of our apparatus shown located in a vertical position;

Fig.7 is an en-largedsection taken on a line, and in the direction, indicated by the arrow 7 inhFig. 6, and showing amodified formof the'gas and air passages and the dust-collecting means; and

Fig. 8 is an enlarged sectionalview taken on the line 8; 8 of Fig. 6 showing in eleva- I tion the spacing meansfor the curved dustdrier, in some forms of which the gases carry 'deflecting plates.

oil" a certain amount of coal dust in suspen-' Referring now to Figure 1', the hot gases 'as discharged from the furnace or through the coal Y drier, enter the preheater at '2, and

pass out at 8, while the air to be heated enters diagonallyin the area'covered by the diagonal dotted lines-in Figure 1, which latter indicate dust catch1ng flanges or channels 9. These dust-collecting channels 9, asindicatedin Figuresl'to l, may be welded or otherwise attached'by their flanges 13'to the-heater elementsor plates 7 along the line of the corrugations of said plates, and they, therefore, each extend diagonally downwards in a planeparallelwith thepath of flow of the. flue gas, and are adapted to catch the dust, :which is thrown or diverted into them as a resultof the alternate side-to-side defiection of the gas stream by the corrugated lower ends 11 (see Figs. 1 ande). Figure 5 illustrates howithe Welding flange 13 of each channel or angle 9 is bent back asat 13a, at thelower end 11 of the channel, in order to extend the dust-guiding channel right into the collecting chamber 10. 5

Supporting and spacing rods 1 1Jand'15 (see Figs. 1, 2, and 3a), the former extending through the gas passages-.6 and the latter through the air passages 12, maintain the plates 7 in their proper alignment and relative positions. These rods or bars extend longitudinally of the apparatus and consequently diagonally with reference to the corrugations of the plates. Those numbered 14 are in contactwith the convex ridges of the corrugations, while those numbered 15 are of a diameter equal to the thickness of the air passages in which they lie. The latter rods are therefore bent in wave lines to conform to the diagonally extending plate corrugations, and they divide the air passages into several channels within the area of the corrugations, that is, from end to end of the rods or from the points 15 to the points 15a (see Fig. 1).

The foregoing construction maintains a good distribution of the air streams over the face of the heating elements 7, by preventing the rising of the heated air to the top of the heating plates it passes between them, and also by virtue of the fact that proper distribution of the air as between the separate channels is obtained by the positioning of the rods in stepped relation as shown in Fig. 1. The rods 14, in the gas passages, being only a fraction of the diameter of the passage, allow free movement of the gases in any direction therein, and since the dustcatching channels 9 will of necessity, divert a certain amount of the gases downward into the collector or chamber 10, we have provided a bat-lie 16, behind which these gases can escape into the by-pass or gas-return pipe 17 through which they are passed back to the gas stream near the gas outlet 3. The, dustcollected in the bin or chamber 10 is removed through the outlet18 at the bottom for disposal.

In the modified form of our invention, as illustrated in Figures 6, 7 and 8, we have shown the apparatus as a whole positioned vertically. The construction, in general, is similar to that of Figs. 1 to 5, having gas inlet 2 and outlet 3, air inlet and outlet 1 and 5, gas passages 6 and air passages 12, clustcatching channels 9, dust collector 10, baffle 16, gas-return conduit 17, and so on. In this construction, however, the heat-transferring elements 7a are fiat-plate passages throughout their length, which are readily available commercially, and the dust-collecting channel members 9 are welded or otherwise attached thereto diagonally by their flanges 13.. Wi hin each gas passage 6 formed by the flat heating plates 7a, is located a separate corru- 23 take a sinuous course in order to perform the function of throwing or diverting the dust into the channels 9. These plates or sheets are corrugated diagonally over the area covered by the channels (see Fig. 6) and are ield in spaced relation between the elements 7a by spacing ears or tongues 19, punched ated plate 76 for causing the gas st-ream to' out laterally,alternately on each side of each such sheet 76, as shown clearly in Figures 7 and 8. 1

From the foregoing explanation of the construction of our combined air heater and dust collector, it will be evident that, in comparison with ordinary installations of separate preheaters and dust collectors, our device has the advantages of lower cost of construction, less total space occupied, adaptability to installation in widely differing space arrangements, higher thermal efliciency, and substantial reduction in total resistance to the passage of the flue gas over installations in which the gas is passed through a. separate heater and a separate dust-collector.

We claim:

1. An economizer for furnaces comprising, in combination, a heat-transforming element, heat conducting dust-collecting means on one side thereof, means for passing waste furnace gases in a sinuous course over said side of said element, and means adapted to pass a current of air to be heated over the other side of said element.

2. In combination, in an air preheater, a curved plate forming a dividing wall between adjacent passages'of the heater, means for a gaseous heating medium through the heater. on one side of said plate, means for passing air to be heated through the heater on the other side of said plate, and dust-collecting means on the gas side of said plate.

' 3. In combination, in an air preheater, a curved plate forming a dividing wall betweenadjacent passages of the heater, means for passing a gaseous. heating medium through the heater on one side of said plate, means for passing air to be heated through the heater on the other side of said plate, and dust-catching channels on the gas side of said plate and extending downwardly through, and forwardly inthe direction of, the gas flow. I

4. In combination, in an air. preheater, a corrugated plate forming a dividing wall between adj acentpassages of the heater, means for passing a gaseous heating medium through a passage on one side of said plate, means for passing air to be heated through a passage on the other side of said. plate, and dust-collecting channel means on the gas side of said plate and extending downwardly through, and forwardly in the direction of, the gas flow, said channel means and said plate corrugations being parallel to each other.

5. A combined dust-collector and air-preheater for furnaces, comprising a plurality of plates forming passages between them, means for passing hot furnace gases through alternate passages, means for passing air to be heated through adjacent alternate passages, and dust-collecting channel members in said gas passages, said channels lying diagonally in a vertical plane in the direction of the gas currents. I

6. A combined dust-collector and air-preheater for furnaces, comprising a plurality of plates forming passages between them, means for passing hot furnace gases through alternate passages, means for passing air to be heated through adjacent alternate passages, dust-catching channels in said passages extending diagonally downwardly and forwardly relative to the flow of gas, and a dustcollecting pocket below them.

7. A. combined dust-collector and air-preheater for furnaces, comprising a plurality of plates forming passages between them, means for passing hot furnace gases through alternate passages, means for passing air to be heated through adjacent alternate passages, dust-catching means extending downwardly through said gas passages, a dustcollecting chamber at the lower end of said means, and a passage from said chamber to carry off any gases diverted with the dust.

8. A combined dust-collector and air-preheater for furnaces, comprising a plurality of plates forming passages between them, means for passing hot furnace gases through alternate passages, means for passing air to stroying the function of the intercepting device.

In testimony vwhereof I have hereunto HARRY T. BERNHARD.

be heated through adjacent alternate passages, dust-catching means extending downwardly through said gas passages, a dustcollecting chamber at the lower end of said means, and aby-pass from said chamber to the gas stream to return any gases diverted. with the dust.

9. In apparatus of the character described, a casing, a plurality of plates forming a plurality of passages therethrough, and spacing means between adjacent plates, the spacing means in alternate passages dividing each of said passages into a plurality of channels having their ends in stepped relation.

10. In apparatus of the character described, in combination, a casing, a gas inlet thereto, a gas outlet therefrom, an air inlet, an air outlet, a plurality of plates in the easing dividing it into a plurality of alternate gas and air passages, said plates being diagonally corrugated over a part of their area, and spacing rods in the passages between the plates, said rods in alternate passages being bent in wavelines to fit the corrugations of' the plates, and dividingsaid passages each into a plurality of channels. 11. In combination with a fluid heater having a passage for the fluid to be heated and 

